The fastest way to give a bunch of users the same permissions is by creating a user group, adding all the users to it, and then applying the appropriate permissions to the group. The moment a user is a member of a user group, that individual will immediately have the same access as everyone else in the group (e.g. Administrators, International Dialers, etc).
1. Click User Groups in the left sidebar.
2. Click [ADD GROUP].
3. Enter a Name for the user group.
4. Click the checkmark icon.
5. Click the new user group to edit its settings.